Xanthene

About: Xanthene is a research topic. Over the lifetime, 2132 publications have been published within this topic receiving 34803 citations. The topic is also known as: Xanthene & dibenzo[a,e]pyran.

Near-infrared fluorescent pigment, diagnostic imaging material, and diagnostic imaging method

Abstract: PROBLEM TO BE SOLVED: To provide a near-infrared fluorescent pigment having a fluorescent wavelength on a longer wavelength side than fluorescein and inverted U-shaped naphthofluorescein (1) which are already known; and to provide a diagnostic imaging material, which contains such a near-infrared fluorescent pigment, and a diagnostic imaging method which is carried out by using such a diagnostic imaging material.SOLUTION: Linear naphthofluorescein (2) has the condensation positions of two benzene rings at [b, i] of xanthene among naphthofluoresceins having structure in which two benzene rings are added to both the sides of the xanthene skeleton of fluorescein, respectively, the naphthofluorescein (2) having a fluorescent wavelength on a longer wavelength side than already known fluorescein and inverted U character-type naphthofluorescein (1).

Preparation and reactions of anthrone and xanthene―triphenylphosphonium salts. A facile and efficient approach to alkylation and alkenylation of cycles and heterocycles

Abstract: Triphenylphosphonium salts (3) of 10,10-dibromoanthrone (1a) and 9,9-dichloroxanthene (1b) were prepared and generalized reactions for the salts (e.g. Wittig reaction, hydrolysis and thermolysis) were suggested and illustrated using the aforementioned species.

Benzoates of Basic Dyes

Abstract: 1,162,808. Benzoates of basic dyes; inks. BADISCHE ANILIN- & SODA-FABRIK A.G. 29 Dec., 1966 [30 Dec., 1965], No. 58121/66. Headings C4A and C4P. The invention comprises benzoates of basic dyes of the diphenyl or triphenyl methane, xanthene, monoxazine and heterocyclic methine series, wherein the benzoate radical is derived from a benzoic acid of the formula wherein X represents H, halogen, amino, OH, OCH 3 , alkyl, C 6 H 5 CO, CH 3 CO or an esterified carboxylic group and Y represents H, Cl, amino or OH; which are soluble in alcohols but practically insoluble in water. They may be obtained by reacting a salt of a basic dye with a salt of a benzoic acid of the above formula or by reacting a free dye base with a free benzoic acid of the above formula. Examples are given for the production of the compounds. Printing inks and ball point pen inks are obtained from the above dye salts. In Example (7) a flexographic printing ink is obtained by dissolving a dye in alcohol, ethyl cellosolve and shellac, and (8), (9) a glycol printing ink and a ball point pen ink are obtained by dissolving dyes in a phthalic acid hexanetriol ester and diethylene glycol.